An inflammatory bowel disease is a disease that causes the chronic inflammation of unknown etiology into intestines and it can be classified into ulcerative colitis and a Crohn's disease. The ulcerative colitis is a disease causing the continuous development of erosion or ulcer on a colonic mucosa and causes hematochezia, mucous and bloody stool, diarrhea, and abdominal pain, and if severe, the systemic symptoms, such as, fever, weight loss, and anemia, may occur. Moreover, the Crohn's disease is a disease that causes the lesions, such as, ulcer, in a discontinuous way on random sites of the digestive tract from mouth to anus, and along with abdominal pain, diarrhea and hematochezia, it causes the symptoms, such as, fever, weight loss, lethargy, and anemia, if it is severe. Both the ulcerative colitis and Crohn's disease are a chronic intractable disease, in which the symptoms are temporarily improved, but repeatedly recur. Although neither the cause nor patho-physiology of the inflammatory bowel disease was clearly identified yet, it is estimated that the genetic factors, the environmental factors, such as, intestinal bacteria or food, and the immunological factors are involved in combination in the pathogenesis.
In the past, it was known that westerners are more prone to have ulcerative colitis and Crohn's disease, but due to the change of life habit such as eating habits, the number of patient is dramatically increasing in Asia including South Korea. Nevertheless, due to uncertain etiology, the fundamental methods of treatment have not been established yet and therefore, some drugs are currently being used that are only able to delay and palliate the progression of symptoms and prolong such states as long as possible but not able to aim for complete treatment. As drugs for such conservative therapy, an aminosalicylic acid, adrenocortical steroid, immunosuppressant, and a TNF-α monoclonal antibody are mainly used, but a number of side effects are being reported. For instance, the side effects, such as. nausea, vomiting, loss of appetite, rash, headache, hepatic dysfunction, leucopenia, abnormal erythrocyte, proteinuria and diarrhea are being reported for sulfasalazine that is frequently used as aminosalicylic acid. Prednisolone, which is an adrenocortical steroid is used by oral administration, enema, suppository and intravenous injection, but has intense side effects such as gastric ulcer or necrosis of the femoral head caused by long-term use. Although Inflixima, a TNF-α monoclonal antibody, was approved by FDA of the United States in 1998 as a treatment for Crohn's disease and used to treat patients with Crohn's disease, side effects such as pancytopenia, drug induced lupus, hepatitis B and reactivated tuberculosis are occurring. Also the U.S FDA is warning physicians that risk of lymphoma and other types of cancers can be increased, if Infliximab and other types of Tumor Necrosis Factors (TNF) are used.
Therefore, the development of new treatment for an inflammatory bowel disease that is more effective, safer and has fewer side effects than currently available treatments for an inflammatory bowel disease is urgently needed.